RESUMO
Ethanol (EtOH) consumption is a primary health risk worldwide, which generally starts during adolescence in a binge pattern (i.e., the episodic consumption of high amounts). Binge EtOH consumption can lead to modifications of the innate and adaptive immune responses, including fever. The present study evaluated the febrile response that was induced by lipopolysaccharide (LPS) and prostaglandins E2 (PGE2) and the mechanisms of thermoregulation in adolescent rats that were exposed to EtOH in a binge-like pattern. Male Wistar rats were treated with an intraperitoneal (i.p.) injection of EtOH or saline on postnatal days (PND) 25, 26, 29, 30, 33, 34, 37, and 38. On PND 51, they received a pyrogenic challenge with LPS (i.p.) or PGE2 (intracerebroventricular) to induce a febrile response. Interscapular brown adipose tissue (BAT) mass and uncoupling protein (UCP) activity in isolated mitochondria were evaluated on PND 51. The rats were then subjected to cold challenges to analyze adaptive thermogenesis. Intermittent EtOH exposure during adolescence impaired the LPS- and PGE2-induced febrile response 12 days after the end of EtOH exposure. Ethanol exposure decreased interscapular BAT mass, oxygen consumption, and UCP activity in isolated mitochondria, resulting in an impairment in thermogenesis at 5 °C. No morphological changes in BAT were observed. These findings indicate that binge-like EtOH exposure during adolescence impairs thermoregulation by reducing BAT mass and function. This reduction may last for a prolonged period of time after the cessation of EtOH exposure and may affect both cold defenses and the febrile response during the development of infectious diseases.
Assuntos
Tecido Adiposo Marrom/metabolismo , Consumo Excessivo de Bebidas Alcoólicas/metabolismo , Etanol/administração & dosagem , Febre/metabolismo , Termogênese/fisiologia , Tecido Adiposo Marrom/efeitos dos fármacos , Fatores Etários , Animais , Etanol/toxicidade , Febre/induzido quimicamente , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Ratos , Ratos Wistar , Termogênese/efeitos dos fármacosRESUMO
AIMS: The aim of this study was to investigate the dynamic changes in the bacterial structure and potential interactions of an acclimatized marine microbial community during a light crude oil degradation experiment. METHODS AND RESULTS: The bacterial community effectively removed 76·49% of total petroleum hydrocarbons after 30 days, as evidenced by GC-FID and GC-MS analyses. Short-chain alkanes and specific aromatic compounds were completely degraded within the first 6 days. High-throughput sequencing of 16S rRNA gene indicated that the starting bacterial community was mainly composed by Marinobacter and more than 30 non-dominant genera. Bacterial succession was dependent on the hydrocarbon uptake with Alcanivorax becoming dominant during the highest degradation period. Sparse correlations for compositional data algorithm revealed one operational taxonomic unit (OTU) of Muricauda and an assembly of six OTUs of Alcanivorax dieselolei and Alcanivorax hongdengensis as critical keystone components for the consortium network maintenance and stability. CONCLUSIONS: This work exhibits a stabilized marine bacterial consortium with the capability to efficiently degrade light crude oil in 6 days, under laboratory conditions. Successional and interaction patterns were observed in response to hydrocarbon consumption, highlighting potential interactions between Alcanivorax and keystone non-dominant OTUs over time. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results contribute to the understanding of interactions and potential roles of specific members of hydrocarbonoclastic marine bacterial communities, which will be useful for further bioaugmentation studies concerning the associations between indigenous and introduced micro-organisms.
Assuntos
Bactérias/metabolismo , Consórcios Microbianos , Petróleo/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Golfo do México , RNA Ribossômico 16S/genéticaRESUMO
Araucaria angustifolia (Bert.) O. Kuntze is a species critically endangered of extinction and its development and propagation is strongly affected by abiotic stress. We have previously shown the activation of uncoupling protein in A. angustifolia embryogenic stem cells subjected to cold stress. Now, we have furthered those studies by exposing these cells to cold stress (4 ± 1 °C for either 24 or 48 h) and evaluating parameters associated with oxidative stress and alterations in the cellular and mitochondrial responses. Cold stress affect the H2O2 levels and lipid peroxidation increased after both stress condition, an effect associated with the decrease in the activities of peroxidases, catalase and ascorbate/dehydroascorbate ratio. On the other hand, the activities of ascorbate peroxidase, monodehydroascorbate and dehydroascorbate reductases increased as an indication of adaptation. Another important impact of cold stress conditions was the decrease of external alternative NAD(P)H dehydrogenases activity and the increase of mitochondrial mass. These results show that cold stress induces oxidative stress in A. angustifolia embryogenic cells, which results in activation of the glutathione-ascorbate cycle as a compensation for the decrease in the activities of catalase, peroxidases, and external NAD(P)H dehydrogenases. Our results contribute to the understanding of the pathways that gymnosperms employ to overcome oxidative stress, which must be explored in order to improve the methods of conservation and propagation of A. angustifolia.
Assuntos
Adaptação Fisiológica , Resposta ao Choque Frio , Conservação dos Recursos Naturais , Células-Tronco Embrionárias/metabolismo , Estresse Oxidativo , Traqueófitas/citologia , Traqueófitas/embriologia , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Traqueófitas/crescimento & desenvolvimento , Traqueófitas/fisiologiaRESUMO
Using the k-NN classifier in combination with the first Minkowski metric, in addition to techniques of digital image processing, we developed a computational system platform-independent, which is able to identify, to classify and to count five normal types of leukocytes: neutrophils, eosinophils, basophils, monocytes and lymphocytes. It is important to emphasize that this work does not attempt to diferentiate between smears of leukocytes coming from healthy and sick people; this is because most diseases produce a change in the differential count of leukocytes rather than in theirs forms. In the other side, the system could be used in emerging areas such as the topographic hematology and the chronobiology.
Mediante un clasificador k-NN en combinación con la primera métrica de Minkowski y técnicas de procesamiento digital de imágenes, se desarrolló un sistema computacional independiente de la plataforma, capaz de identificar, clasificar y contar cinco formas normales de leucocitos: neutrófilos, eosinófilos, basófilos, monocitos y linfocitos. Es importante enfatizar que este trabajo no intenta diferenciar entre muestras de leucocitos provenientes de gente sana y enferma, debido a que la mayoría de las enfermedades se detectan principalmente por un cambio en el conteo diferencial de leucocitos más que por cambios en su forma. Finalmente, el contador de leucocitos puede ser usado en áreas emergentes como la hematología topográfica y la cronobiología.
RESUMO
Beta-sitosterol (BS) is a compound that has shown various activities potentially useful for human health. In the present study, we determined its antigenotoxic capacity and lymphocyte induction potential in mouse as well as its capacity to trap free radicals in vitro. BS, in doses from 200 to 1,000 mg/kg, was able to significantly reduce the frequency of sister chromatid exchanges induced by 10 mg/kg of doxorubicin (DX) in bone marrow cells. The same range of BS doses also gave rise to a strong reduction in the rate of micronucleated, polychromatic erythrocytes induced by DX. In addition, we determined an increase in the production of lymphocytes in mice administered with BS. By means of the DPPH assay, the compound was shown to trap free radicals in a concentration dependent manner as high as 78.12% using 250 mug/ml. Our research established three relevant biological activities of BS which show its potential as a chemopreventive agent.
Assuntos
Antimutagênicos , Antioxidantes/farmacologia , Linfócitos/efeitos dos fármacos , Substâncias Protetoras , Sitosteroides/farmacologia , Animais , Antibióticos Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/farmacologia , Sequestradores de Radicais Livres/farmacologia , Contagem de Linfócitos , Masculino , Camundongos , Testes para Micronúcleos , Troca de Cromátide Irmã/efeitos dos fármacosRESUMO
Beta-sitosterol (BS) and pteropodine (PT) are constituents of various plants with pharmacological activities potentially useful to man. The chemicals themselves possess biomedical properties related to the modulation of the immune and the nervous systems, as well as to the inflammatory process. Therefore, safety evaluation of the compounds is necessary in regard to their probable beneficial use in human health. The present study evaluates their genotoxic and cytotoxic potential by determining the capacity of the compounds to induce sister chromatid exchanges (SCE), or to alter cellular proliferation kinetics (CPK) and the mitotic index (MI) in mouse bone marrow cells. Besides, it also determines their capacity to increase the rate of micronucleated polychromatic erythrocytes (MNPE) in peripheral mouse blood, and the relationship polychromatic erythrocytes/normochromatic erythrocytes (PE/NE) as an index of cytotoxicity. For the first assay, four doses of each compound were tested: 200, 400, 600, and 1000 mg/kg in case of BS, and 100, 200, 300, and 600 mg/kg for PT. The results in regard to both agents showed no SCE increase induced by any of the tested doses, as well as no alteration in the CPK, or in the MI. With respect to the second assay, the results obtained with the two agents were also negative for both the MNPE and the PE/NE index along the daily evaluation made for four days. In the present study, the highest tested dose corresponded to 80% of the LD(50) obtained for BS and to 78% in the case of PT. The results obtained establish that the studied agents have neither genotoxic nor cytotoxic effect on the model used, and therefore they encourage studies on their pharmacological properties.
RESUMO
MI-D (4-phenyl-5-(4-nitro-cinnamoyl)-1,3,4-thiadiazolium-2-phenylami ne chloride), a new mesoionic compound, depressed the phosphorylation efficiency of liver mitochondria as deduced from an accentuated decrease of the respiratory control coefficient and ADP/O ratio. Analysis of segments of the respiratory chain suggested that the MI-D inhibition site is further on than complex I and between complexes II and III. The transmembrane electrical potential (delta psi) was collapsed dependent on MI-D concentration. ATPase activity was dramatically increased by MI-D in intact mitochondria, but inhibited in carbonylcyanide p-trifluoromethoxyphenylhydrazone (FCCP)-uncoupled mitochondria. These results suggest that MI-D acts as an uncoupler agent, a property closely related to its structural characteristics.
Assuntos
Respiração Celular/efeitos dos fármacos , Cinamatos/farmacologia , Mitocôndrias Hepáticas/metabolismo , Tiazóis/farmacologia , Desacopladores/farmacologia , Difosfato de Adenosina/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Relação Dose-Resposta a Droga , Transporte de Elétrons/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Masculino , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias Hepáticas/enzimologia , Fosforilação Oxidativa/efeitos dos fármacos , Oxirredutases/metabolismo , Oxigênio/metabolismo , Ratos , Ratos Wistar , Ácido Succínico/metabolismo , TiadiazóisRESUMO
Dentro de las cirugías cardiacas la valvular es una de las más frecuente en el adulto; para obtener buenos resultados se requiere de medidas especiales y educación del paciente. Por esta razón se diseño un estudio prospectivo y observacional que consta de un cuestionario de 11 preguntas sobre el conocimiento de la enfermedad vascular, que se aplicó a 126 pacientes con prótesis vascular cardiaca. En promedio respondieron cinco preguntas, ninguno contesto las 11. Este estudio demuestra el poco conocimiento de los pacientes acerca de su enfermedad, el cual los médicos también deben intervenir
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Relações Profissional-Paciente , Educação de Pacientes como Assunto , Inquéritos e Questionários , Conhecimento , Endocardite/prevenção & controle , Próteses Valvulares CardíacasRESUMO
Low-density lipoprotein (LDL) could be used as a carrier of chemotherapeutic agents to neoplastic cells that overexpress LDL receptors (rLDL), but LDL is difficult to obtain and handle. Recently, it was observed that a protein-free emulsion resembling the lipid portion of LDL (LDE) behave like native LDL when injected into the bloodstream. In this study, the evidence that LDE is taken up by rLDL was expanded by comparing LDL and LDE plasma decay curves in rabbits and by competition experiments with lymphocytes. To verify whether LDE could be removed from the plasma by neoplastic cells with increased rLDL, LDE labeled with 14Ccholesteryl ester was injected into 14 patients with acute myeloid leukemia (AML) and into 7 with acute lymphocytic leukemia (ALL). In AML rLDL expression is increased but in ALL it is normal. LDE plasma fractional clearance rate (FCR, in h-1) was calculated from the remaining radioactivity measured in plasma samples collected during 24 h following injection. LDE FCR was 3-fold greater in AML than in ALL patients 0.192 +/- 0.210 (SD) and 0.066 +/- 0.033 h-1, respectively, P < 0.035. When LDE injection was repeated in 9 AML patients in hematological remission, LDE FCR diminished 66% compared to the pretreatment values (from 0.192 +/- 0.210 to 0.065 +/- 0.038 h-1, P < 0.02), so that it could be estimated that nearly 66% of the emulsion was taken up by AML cells and only 34% by the normal tissues. As expected, LDE FCR was unchanged in 4 patients with ALL in hematological remission (0.069 +/- 0.044 h-1). Gamma camera images obtained 6 h after the injection of 99mTc-label LDE into one patient with ALL showed biodistribution similar to that of LDL. In one AML patient LDE was comparatively more concentrated over the areas corresponding to the bone marrow infiltrated by AML cells. Our results indicate that LDE FCR is increased in a disease known to contain malignant cells that overexpress rLDL, suggesting that LDE is taken up by malignant cells with increased rLDL.